1. Field of the Invention
The present invention relates to a disk cartridge apparatus capable of recording an information signal on a signal recording layer or reproducing an information signal from the signal recording layer by irradiating laser beams on the signal recording layer of an optical disk, for example. More specifically, the present invention relates to a disk cartridge apparatus of a so-called compatible type in which a plurality of disk cartridges having cartridge housings different in size and thickness for storing therein disks having different diameters are selectively loaded on a recording and reproducing apparatus and in which while the disk cartridges different in size and thickness are being loaded on the recording and reproducing apparatus, heights of respective switch detection surfaces of disk cartridges different in size are aligned with a detection switch of the recording and reproducing apparatus.
2. Description of the Related Art
Optical disks capable of reproducing information from a recording medium or recording information on the recording medium by optical beams have heretofore been proposed as recording mediums for a variety of information such as audio information or video information. This kind of optical disk can be formed of a single flat plate-like disk and hence it is easy to handle. Moreover, because it has a large recording capacity as compared with other recording medium such as a magnetic tape, it is widely applied as a recording medium for audio information, video information and data processed by a computer.
A demand for more miniaturizing a recording and/or reproducing apparatus using an optical recording medium such as an optical disk is increasing because a space in which the recording and/or reproducing apparatus is assembled into an information processing apparatus such as a computer should be reduced more.
In order to miniaturize the recording and/or reproducing apparatus, the recording medium also should be miniaturized and a demand for a high storage capacity recording medium also is increasing. To this end, there have been proposed a plurality of kinds of disk cartridges having cartridge housings of different size and different thickness to store therein disks having different diameters as recording mediums. The assignee of the present application has previously proposed these disk cartridges as Japanese Patent Application No. 11-176029.
It has been customary that a disk cartridge has mis-erase protection detection hole and a disk discrimination detection hole. These detection holes are generally discriminated by depressing a detection pin of a mode detection switch on a drive apparatus side. However, a tolerance of a height of the detection pin of the mode detection switch falls within approximately (0.1 mm and an accuracy of the detection pin is low as compared with surrounding parts. There is then a large possibility that these detection holes will be discriminated erroneously.
When the above disk cartridges which are different in size and thickness can be loaded onto and driven by a single drive apparatus, if detection heights of mis-erase protection detection holes, for example, of the disk cartridges are different, there is then the risk that the detection holes will be discriminated by the mode detection switch erroneously more frequently. In a floppy disk or a disk cartridge such as an MD (mini disc) and an MO (magneto-optical disk), for example, there is no way to avoid the above risk on the assumption that the disk cartridges of different size and different thickness are driven by a single drive apparatus.
The present invention is made in order to solve the above problems and is intended to provide a disk cartridge apparatus in which respective switch detection planes of disk cartridges can be made flush with a mode detection switch of a drive apparatus when a plurality of disk cartridges which are different in size and thickness are loaded onto the drive apparatus.
In order to solve the above object, a disk cartridge apparatus according to the present invention is comprised of a plurality of disk cartridges having cartridge housings, each being different in size and thickness, to store therein disks having different diameters, a plurality of detection holes having switch detection surfaces for discriminating modes of the disk cartridges defined on one surface of each of the disk cartridges different in size and thickness and a recording and reproducing device including a recording and reproducing portion for selectively loading thereon the plurality of disk cartridges different in size and thickness and recording and/or reproducing the disks having different diameters, the recording and reproducing device including, detection switches for discriminating modes of the disk cartridges by detecting the plurality of detection holes of said disk cartridges different in size and thickness and a position reference portion for properly deciding on the positions and heights of the disk cartridges different in size and thickness relative to the recording and reproducing device, wherein when said plurality of disk cartridges different in size and thickness are loaded on the recording and reproducing device, the height of the detection switch surface of a disk cartridge having a large diameter and the height of the switch detection surface of a disk having a small diameter are aligned with each other with respect to the detection switch.
According to the above disk cartridge apparatus, even when the respective switch detection surfaces of the disk cartridges different in size and thickness are different in height, the disk cartridges are loaded on the recording and reproducing apparatus and have positions thereof decided on by the position reference portion so that the respective switch detection surfaces of the disk cartridges can be aligned with the detection switch. Thus, it is possible to avoid the detection holes of the disk cartridges different in size and thickness from being discriminated erroneously without changing the heights of the detection switches.